Apparatus for treating materials



Nov. 26, 1940. F. s. sMm-l APPARATUS FOR TREATING MATERIALS Filed Aug. 6, V1937 5 Shee'ts--SheetI 1 ATTO R N EY Nov. 26, 1940- F. s. SMITH APPARATUS FOR TREATING MATERIALS Filed Aug. 6, 1937 5 Sheets-Sheet 2 QN 3Q N ww mw 2; @y a. Q a S @W m Q s@ v NQ y www W\ fh A/ QM. NN NN j el;

2 M R s mm NS R w. Mo m5 um @f M Y Ff@ @NN Nov. 26, 1940. F. s. sMlTH APPARATUS FOR TREATING MATERIALS Filed Aug. 6, 1937 5 Sheets-Sheet 3` Zw/L INVENTOR Franklin 15'. SmL'/z ma, m, im #47ml ATTORNEYS Novo 26, 1940. F. s. SMITH APPARATUS FOR TREATING MATERIALS Filed Aug. 6, 1937 5 Sheets-Sheet 4 INVENTOR alzlz'lz Sm ATTORNEY" Nov. 26, 1940. F. s. sMn'H APPARATUS FOR TREATING MATERIALS 5 Sheets-Sheet 5 Filed Aug. 6, 1937 1 INVENTOR i 'anzZL'n SmL'/z BY @4A amm', UM f/Ayww/ ATTORNEYS Patented Nov. 26, 1940 j" 'f l N Frankuns; smith, Newiiawn,"conn..v

lApplication August s, 1937,'seria1 No. 15%.,99 1

20 Claims.

.Y This inventionrelates to an art and. apparatus vfor treating food and other products and is especially; concerned with sterilizing products by means'of'an electrical discharge. j I One of the objects-.of this invention is to provide athoroughly reliable art and apparatus for subjecting food and other products to a treatment in a dependable and practical manner without injury to the product. Y Another object is to '10 provide an art and apparatus of the above character in whichy food` or other products mayv be subjectedlto an electrical treatment. A stillfurtherlobject is to provide an artand apparatus 0L thel above character wherein food .orother "1B prdductsmaybe sterilized without injuring the product-in any manner. s Another' object is to provide a highly eflicient and thoroughly practical art and apparatus of the above 4characterwhich may be used to "destroy insects orvother life, including all' eggs, larvae, and pupae. Another object is to provide an art and apparatus Vin which these various ad:-

` vantages are obtained and thefvariousfunctions may be readily and eiciently controlled over wide ranges of.usage. Y Y. Another object `is to provide inexpensive apparatus of the Vabove character, small insize-and weight, 'and capable of dependable andsafe operation. Other objects will be in part obvious and in part pointed outhereinafter. l'I'he invention accordingly consists in thefea,- tures of construction, combinations of elements, arrangements of parts and in the several steps andvrelation and order of each of the same to v33 oneor more of the others, all as will be illustrat tively 'described'hereim and the scope of the applic'atior fl which will be indicated in the following claims.

In the accompanyingA drawings in which are shown some of the various possible embodiments o f thenelectrical and mechanical features oi my invention, Y

-`liligure 1 is apfront elevation of the apparatus, some parts being shown diagrammatically, some 45 partsgbeing broken away, and other parts being shown in section; .s

4'Figure 2 is a plan view showingthe electrode structure and the path of the material with cer- 5() tainparts'broken away; n j

l Figure 3 is a horizontal sectional view of an electrode roller and the adjacent portion'of the condenser member which helpssupport it;

Figure 41s a vertical sectional view on the line I-'4of Figure 1, certain parts-being broken away .and others lvomitted-'showing a packageY in lthe ytreatment zone;A g

l Figure 5 is a. sectional view of one of the elecytrode structures; f p 1 .n ,l '..Fgureis aview. with certain parts broken 5 awaygshowing a portion-.of the mounting means for theupper electrode units; l Figure 7is a perspective view of anupper electrode assembly unit; and

Figure .8@.isma perspective view of a modified form offtheupperelectrode'unit. c; Thisapplication is a continuation-impart; yof my copending application 747,441,1iled AOctober 8, 1934, now PatentNo. 2,132,707, issued vQ'ctober I'he,particular embodiment disclosed he in operates,.. to'-pass.products such as packages-fof food through a discharge zonewhereuthey are subjectedl to a highlpotential with the result that f, Vdischarges takejplace within the products.; When this apparatus is used in a manner -explainedjin detail .below, these discharges areol.V a coronalikedisruptive naturetand thoroughly ltreat the entire product. 'l' Ithas beenI found that highly-- practical"and`desirable-results are thus obtained 25 with apparatus which is light in Weight-pornpact, and economical to build and use.l H g Referringnto. Figure 1, tl'1e apparatus. includes upper-and lower electrode structures, generally.v referredto by"E the numeralsk 2 and 14, respec- 30 tively., having a-discharge zione 3, therebetween. Thep'roduct being treated is moved throughfithisv treatment zone and, at the'same time, a highfrequehcy, 'high-potential voltage `is impressed 1 across the two electrode structures so asntozcauser `35 a disruptive corona-like discharge throughl the P1`011Ctj s f The .productv being treated enters themachine at theriglit (see also Figure 2) lllzhroiiggrli opening 2261 ardl'eaves ',tliemachineat the left, through o penig, thus'"mving throughy the machine upon a roller conveyorsystem Whichincludes a group off di'elctrlc rollers 9 at the right, aigroup of electrode rollers I0 at the center, and a group of dielectric rollers Il attheleft.. As will bedescribedill'ater, .movement .of the :product .isobtained byfrotating' the rollers, the, path of the product'being determined in some instances Aby means such as guide rails of dielectric material positioned above the roller conveyor (seezEigu'res 1 and. '2)j2'j-'I'l'1e'se'guide rails are in pairsglthere being a pair'jl32 extending over rizlllersj, a pair H'extending over electrode rollers 10, and a'pair -lfextending over` rollers Il.. vRails [9 are rol tatably 'mounted' irithe adjacent ends of rails 55 rPATENT 'oF-Fica f |32 and |34, rails |34 being supported at the left (Figure l) by brackets |35, and rails |32 being supported at the right by brackets |33.

Rollers 9 and I| and electrode rollers I8 are rotatably mounted, and are rotated by an endless belt I2 which contacts the under side of one end of each roller. Endless belt I2 is carried by pulleys I4 and I6 and is driven, through a speed reduction gear unit and pulley I4, by an electric motor |70 (Figure 2).

The upper electrode structure 2 includes -a plurality of.electrode elements I8 which are rotatably mounted in pairs and in reversed or opposed relationship upon an elongated frame, referred to generally by the numeral 48. Each pairof electrode elements I8 is mounted, as shown in Figure 5, with an electric motor uponan inverted-U-bracket (see also Figure '7) to form an individual electrode mounting unit. i

In this embodiment, the lower electrode structure comprises a plurality of electrode elements I|8 of the type' shown in Figure 3, 'each electrode element being mounted in a dielectric shell II4 and being electrically and mechanically connected to an elongated tube IIV6, tube-extension |20, and shaft member Ill). Eachk of these electrode elements with itsV shell II4 and othersupporting structure formso'ne ofthe electrode rollers l0, which are mounted as shownin Figure 4, being supported at theright upon a vertical condenser member 2?.,v and at the left by a supporting bridge structure,y allto be described vrin detail below. v A

Referring again to Figure '1,the entire apparatus is mounted in a casing 2li) having legs 2I2 and sheet metal walls. The high-frequency, high-potential voltage is produced by `apparatus similar to that shown in myprior PatentNumber 1,975,805, issued October l9, v1934, and is mountedl mainly upon the roof `of casing 2li); there being at the right,` a high-frequency, lowvoltage alternator 2 I8; at the left a'power-factor compensating resonance coil 22|] and other v oltage regulating means; and inthe center, a highvoltage auto-transformer 6. y Suitable control apparatus is mounted in casing 2I0 adjacent "alternator 2|8 and includes switches 2,22 and voltmeter 224. Y A

Auto-transformer 5 is mounted within casing ZIB, and receives the high-frequency', low-voltage 'of alternator 2 I 8 and transforms this intoa highfrequency, high-voltage lwhich is impressed across the electrodes to produce the disruptive corona-like discharge. Auto-transformer 6 is provided with a winding 2E- which is connected at one end with lead 25, at` an intermediate point with tap 24, and at the other end with lead 32. The low-voltage is impressed between tapv24, which enters casing 2|6 throughyterminal 28,`and lead 25` which is grounded at ground connection 3B, the high potential beingvbetween `lead 32 and ground connection 30. t y l I Mounted within casing ZIB below transformer 5, is an insulationrtransformer 36, bymeansof which a suitable voltage is supplied to the motors which rotate the upper electrode elementsV I8. Transformer 36 has a primary'winding 38 `and a secondary winding 40 which are insulated from eachother for theghigh-voltage of auto-transformer 6. P rimary winding 38 is connected by means of suitable leads, vthrough a pair of terminals 42 (only, one of which is found on the drawings) to a source of alternating current (not shown). One terminal ofthe. secondary winding `4|), of transformer 36, is connected to lead 32and 'trode structure 4.

the other terminal is connected to a lead 44. Leads 32 and 44 extend downwardly from casing 2 IS through high-potential terminal 34 and carry the high side of the high-frequency, high-potential to the electrode, and at the same time, carry a suitable voltage to run the motors which rotate the electrode elements I8, in a manner to be presently described. While transformer 33 is used herein only for insulating purposes, it may also be used to raise or lower the voltage being delivered to theelectrode motors.

For obtaining certain advantages, an air condenser structure is provided in series with the discharge zone which includes a plurality of Ver- `tical condenser members 22 (best shown in Figure 4) which cooperate with the back Wall 2|4 *of the sheet metal covering. Vertical condenser members 22 are supported individually upon a dielectric bridge structure |24 (see also Figure l), each vertical condenser member Supporting one end of, and being electrically connected to, the electrode element of one electrode roller I0.. In thismanner, each lower electrode is connected in series with an individual condenser comprising its supporting vertical condenser member 22 and the-portion of casing wall adjacent thereto.

j Referring again to Figure 1, the upper electrode structure 2 is supported from the roof of casing 2|!) by an insulator which'is formed'by cutting segments from a cylinder of insulation Arr'ia'terial `and which has four downwardly extending arms 45. The upper ends of arms 46 are `attached to casing 2|() through a worm-gear ad- `justment capable of regulating the position'of 'electrode ystructure 2 with respect to lower' elec- Integral with the lower'ends of arms 46 is a ring portion 41 to which is rigidly attached the elongated frame 4,8 of electrode structure 2.

Asbest lshown in Figure 2, elongated frame 4,8 comprises a center section formed of two parallel center beams 5 extending across ring portion; 47,v and two end sections 49 which are in alignment with center beams 5| and extend to the right and left therefrom beyond ring portion 4l (see also Figure l). Center beams 5| are provided with flanges 5I extending beneath ring portion 41 and the adjacent ends of end portions 49;4 end portions 49 are provided with flanges 49' which extend over ring portion 41. Suitable set screws hold portions 49 and center beams 5| ,in this interrltting relationship, thus, rigidly attachingelongated frame 48 to ring portion 41. As pointed out above, each of the electrode assembly units, shown in Figures 5 and 7, is

56 is provided along its sides with ribs 58 which l are received in grooves 50. In assembly, the cross-frame 56 of each electrode assembly unit is pushed. into the end of channel 51 with ribs 58 interengaging with grooves 50. When all of the electrodeassembly units are in position, static shields. |02 are secured in place by means of screws |33. Static shields |02 perform thefunction of retaining the electrode assembly units in place and also shield the upper electrode' struc-"- Cil condenser 253 and safety vfuse 24mountelina ;casing 252, Leads 99;from themain'windings of fthesslx electrode* assembly unitslare all connected ture 2 to assist in providing uniform treatment .and to avoid sparking. n v .-j :f

Referring againto- Figure-,5, rigidly, mounted onthe lower ends of arms 5 2 and 1543is a vmotor deadshaft 69, which provides `mounting-means fortheelectrode motor` and carries ajffpairfof ,electrode elements I8, (see also Figure1)f. "The motor stator core 64, carrying stator Windings', is mounted at the center of 'shaft 60gbetween flange 62, at the left, and nut 68vandlock `washer 1Il,atl the right. l l. g'

The rotor of the electrode motor is carried in -a drum-like casing 1I having a cylindricalshell portiony 16 and endframes'14. :Casing 1Iris mounted through end frames 14 Aupon ballbear.-l ing units 12 which are carried byshaft 6I).V End frames 14 are provided'with anges Which'extend into the ends of shell 16 and aref held in place by'screws 11. Mounted in the center of' rotor shell 16, and surrounding stator core 64, is' rotor core 18. Rotor core 18 is held in placel against shoulder 80, at the left, by ring'82, `at the right, which is secured by a plurality of screws 84 extending inwardly from shell 16. Rotor core 18 carries a squirrel-cage winding having endrings 19 and cross-bars (not shown).

The two electrode elements I8 are mounted between shoulders 86 upon shell 16 and flanges 88 upon end frames 14. 'I'hese two 'electrode ele-v ments I8 are similar but are positioned in opposite relationship (see also Figure V1)l and held from relative movement'by key 90 (Figure 5). Key 90 is mountedv 4upon shell l16 and extends through slots in the adjacent edges of electrode elements I8. Assembly of toroidal electrode elements I8 and end frames14 upont rotor shell 16 is facilitated by pins i12-which extend from* the ends of rotor shell 16 throughy holes in end 1frames 14. y l

In additionto electrical advantages, this particular method of mounting the two' electrode elements I8 gives the rotor units a dynamic balance. However, adjustment to compensate for any deviation from accurate dynamic balance may be facilitated by drilling holes in end frames 14. Cover plates 94 are heldin place'upon end frames 14 by suitable screws. n

In this embodiment, stator windings 66' (Figure 5) comprise a starting windingl and anmain winding, one lead from each of 'whichis attached to shaft 69 through clip 96.. The other end of the starting winding is connected'to a lead 98, and a lead 99 is connected to 'the other end of the main winding. Leads`98 and`99 extend to the left through a suitable opening in shaft 60 and upwardly through amgroove |80 in the outer face of arm-52. In assemblyarm 52 is in contact with the adjacent arm of the next electrode assembly unit,'thus closing groove |08 and completing a conduit for leads 98 and 99 from within casing 1I to elongated fr"ar1:ref48. A if AReferring to the completev assembly iny Figure 1, wherein certaintofnthe electrical elements are shown diagrammatically, mounted atQthe'right upon` the ring portion 41 ofthe insulating sup-- port is a casing 252 (shown in broken lines) Ywhich encloses a condenser 253 anda safetylfuse, 25,4. The leads 98 from the starting winding'sfoifthe three electrode assembly units attharightlare connected to lead 44 through this condenservand this safety fuse. In a like manner, the starting windings of the threeelectrode assembly units on the left are connected to vlead 44 througha directly to lead 44.- i Thus, one side of each of the starting andmain windings is lconnected'to one sideofithe secondary winding of insulation transformer36. .Y

f Aspointedlout' above,v the other sideV ofthe secondary winding` of insulation 'trans'forxnerr 36 is connected to lead 32 and this lead is electrically'connected to one side of each of thestarting and running windings of the Various electrode -as'- sembly units. This 'connection between lead32 and each of the windings is madebyl'cnnecting leadV 32 directly to elongated frame48 which,v irl turn, is'el'ectrically connected through the mechanical lcontacts to the structural elements'of each of' thelelectrode assembly funits'; this' "coni nectionfto `each unit is through its inverted-'Ul minal 34 to elongated frame 48 Lof theupperl electrodestructure 2; Because the'various ele'- ments of the entire upper electrode'structure'z are electrically interconnected through rthe sup'- porting mechanical contacts, an electrical connection is maintained between'lea'd 3.2 and-the .electrode elements I8; this connection is through' the inverted-U-brackets, the ydead shafts pgthe ball bearing units 12 and casings`1l. tAccordingly, all of the electrode elements I8 are maintained at substantially the same potential, the potential of the' high side of the auto-tiansfonnerl 61T 'f As pointed out above, electrode element" o (Figure 5)r are structurallyA similar, but. are mounted in reversed or opposed relationship (see also-Figures land 7). Each electrodejelement I8 is a metallic shell having a toroidal discharge surface, the axis of which is at ancangle'ltoithe axisv of rotation. The discharges between Ythe lower lelectrode structure 4 and leach rotating electrode element I8 are at all'tim'es concentrated at th portion of the surface ofthe electrode elle-4 ment I8 nearest the lower electrode structure!! which shall be referred to| as the vactive vdis?` charge surface?" Dueito rotation of electrode element 18, the active discharge surface l.is vconstantly changing;I and due to the'angular rela. tionship ,between the toroidalV vdischargejsurface andlits axis of rotation, the activefdischarge surf face' is constantly moving laterally with'orfspect to the lower electrode structure .4., .DE

`with one ofi the units inthe position shown-in Figure 5, the active discharge surfacesA oftheotwo electrode elements I8 are adjacent ,each other; near the central portion of casing 1 I During the rotation of the electrode unit through vclrom the Vposition shown in Figure 5, the portions of the electrode elements I 8 at the top Aare moved in Figure 5, and the active discharge surfaces are moved toward the central portion vof casing 1I again. It is thus seen that the active discharge surface on the electrode element I8 at the right has moved to the right and then to the left, while the active discharge surface of the electrode element I8 at the left has moved to the left and then to the right. Thus, during rotation of the electrode elements I8, the active discharge surfaces are constantly oscillating in lateral directions.

As pointed out above, the lower electrode structure 4 (Figure 1) comprises a plurality of electrode elements H8 (see also Figure 3), each of which forms a part of an electrode roller I0; the outer casing of roller I0 comprises dielectric shell H4 of a material such as quartz or low powerfactor glass. Dielectric shell I|4 is hollow with the left end closed and reduced to form a bearing portion |08. Electrode element H8 is rigidly attached to a tube-extension |20 by way of a tube H6, all of which parts are positioned along the axis of dielectric shell H4; tube-extension |20 is cemented in place. Moisture-free ground quartz surrounds tube H6 and electrode element H8 in a manner to be more fully pointed out hereinafter. Near the left end of tube-extension |20 are two radially extending holes I2I forming passageways to the body of ground quartz. Adjacent holes |2I is a sealing cork |22, and a pivot shaftl IIO fits within tube-extension |20 being held in place by a set screw H0. A ball support H2 is secured to pivot shaft IIO and rests in a socket in reenforcing member |23 to assist in supporting roller I0.

In assembly of an electrode roller I0, thevarious elements are dried and the metallic unit, comprising the electrode element H8, tube IIB, and tube-extension |20, is properly positioned within dielectric shell I I4 and secured in place by cement around tube-extension |20. With the roller standing on its reduced end portion, |08, ground quartz is poured into tube-extension |20 and through holes |2I, until it entirely surrounds electrode element H8 and tube H6; sealing cork |22 is then driven into place by pivot shaft H0 which is secured in place by set screw I I0'. In this manner, electrode rollers of highly practical and sturdy construction are provided which `are eflicient in supporting and moving the product during treatment, and, at the same time, form the lower electrode and dielectric structure.

These electrode rollers I0 are mounted in parallel relationship as shown in Figures 2 and 4; the right end (Figure 4) of each roller is mounted upon and electrically connected to vertical `condenser members 22 by pivot shafts H0; and the left end of each roller is supported upon an insulating bridge structure including a side bridge |04 (see also Figure 1) and a supporting plate III (Figure 4). Supporting plate III is connected to bridge |04 by two rows of brace rods |09 held in place by cap screws 209. This entire bridge structure, including side bridge |04, supporting plate III, brace rods |00 and cap screws 209, is formed from solid dielectric material such as Bakelite L.

Referring to Figures 1 and 2, side bridge |04 is supported at its ends by frames I5 and I1 which carry pulleys I4 and I6 respectively. Supported upon the upper row of brace rods |09 (see also Figure 4) and extending between pulleys I4 and I6 is a belt supporting plate |01 of anti-friction` insulating material. The lupper span of belt I2 lies upon the upper surface of plate |01, and

the adjacent portions of electrode rollers I0 rest upon belt I2. Rigidly mounted upon side bridge |04 to receive the reduced end portion I 08 of each electrode roller I0 is a bearing |06 of insulating material. Bearings |06 are U-shaped to prevent horizontal movement of rollers I0, while permitting -free vertical movement. Thus the eleotrode rollers I0 are held in alignment but rest freely upon belt I2, and, accordingly, movement of belt I2 imparts rotation to rollers I0.

More particularly, electrode rollers I0 are held in alignment with one end supported in a fixed pivot and the other end supported upon the upper span of belt I2. Consequently, if the upper span of belt I2 is moved to the right (Figure 1), due to`clockwise rotation of pulley I4, electrode rollers I0 will be, rotated counterclockwise. Therefore, any materials which rest upon electrode rollers I0, such as packages of a product being treated. will be moved to the left successively across the electrode rollers I0 through the treatment zone.

As pointed out above, the materials being treated are moved to the treatment zone over a series of rollers 9 and are moved from the treatment zone over a series of rollers II. In this embodiment, rollers 9 and II are supported and rotated by structure similar to the supporting structure for electrode rollers I0; thus rollers 9 and I I are carried upon and rotated by the upper span of'belt I2 and held in alignment by suitable bearings |06 (see Figure 2). Rollers 9 are additionally supported in suitable bearings on center bridge |28 while rollers II are additionally supported by similar bearings on bridge |30.

The particular type of vertical condenser member 22 shown (see Figure 4), comprises a metallic tube with rounded plugs 2| and 23 inserted in its ends and a reenforcing member |23 positioned to receive ball support I I2 which carries the adjacent end of electrode roller I0. Vertical condenser member 22 is held in upright position on bridge |24, by screws |26, and bridge |24 is supported upon two legs, shown best in Figure 1. A plurality of brace rods 239 (Figure 4) are provided between support plate III and bridge I 24 and secured in` position by cap screws 240.

In addition to mechanical advantages, rounded plugs 2| and 23 act as static shields for the vertical condenser members 22, the general configuration -of the condenser members 22 being such as to avoid excessive electrical stress and thus prevent sparking. Vertical condenser members 22 are spaced a predetermined distance from the adjacent flat surface of one wall 2|4 of casing 2I0, thus casing wall 2I4 and the condenser elements 22 form individual condensers of predetermined capacity'. Under certain circumstances, an additional at condenser plate may be positioned inside wall 2 I4.

Referring to the right-hand portion of Figure |18, which is mounted between two swinging arms upon shaft and is weighted downwardly. These pulleys |14, |18, and |16 carry hugger belt |82l which contacts the outer surface of belt I2 and exerts pressure thereon so as to hold belt I2 into contact with pulley I4. The tension of hug- Below pulley I6 is a cleaning brush I which is carried by swingingarm |88, pivotally supported apk-1.90, and is held in Contact with belt l2, by. Wght192 so as to remove any undesirable materalsprrompelt lz.

Directly above pulley le is metallicillr/laa oyerjwhich the. packages of material pass as they.

are ischargedfrom the machine. Roller |94 is grounded. and. effectively removes any static.

charge -which may be present on the package.

The structure shown is admirably adapted for use lin treating cylindrical vpackages of materiala. such aspaclfrages 5 as shown in Figure Pack-f ages5, enter the casing endwiseat the right (seealso Figure 1) through opening 226 and move vbetween rails |32 across rollers 9. As a package" movesfont'o thejirstelectrode roller I0 between rotatable'rails I9, as shownin Figure 4, the right side of its forward end contacts the right hand y rail 19.- Rails vI9 fare at an angle to the vinitial path of movement of the package (Figure 2) and consequently further movement v.of the package while`. 'engaging. the right rail I9 (Figure 4) rolls thep'ackage` counterclockw'ise. Rails I9 are so,j positioned with respect to ythe axes of electrode rollers I that a` package moving through the This.. rolling movement of package constantly changes treatment Zone is rolled preferably 180.

the Position of the various portions/of the pack'- age walls.. and the productlwith respect vto. the

electrodes, and as the discharges occur,fthefrela'A tionship between the; discharges and the various portions ofthe product and the package vWalls is constantly changing.

Underso'me circumstances, it visexpedient 4to f treat cylindrical packages of materials after the lid has been placed in position, but not sealed- Rollers and II and electrode rollers I0 tend to;

. push the packages and aid in holding these/uno Y as .falr-lonlzatlon; productsxand it is desirable sealedv llidsin place.

As best shown in Figure l, each electrode ele-` n ment I8 is positioned vdirectly above two electrode rollersI', and the aXis of'rotation of elements- I9r` is atfanangle slightly less than airight angle (Figure`2) with respect tothe' axis, of electrode.-

- out .of .;th e casing-.and vadlscharge fan (not rollers I Il.' Themost effective discharges `from each .electrode element I8 take place betweenit and the' two electrode rollers beneath it, As the eiectivedischarge surface of each electrode. .ele-

ment I8 moves axially with respect. tothe elec-` trode lrollers I0, in the manner explained in "conl nection -with'the discussion of Figure 5, the effec-4 tive discharge surface of electrode element' |33" moves from a position over one electrode roller Ii) t'o'a position over another electrodel roller Il), vIt is thus seen that the distances between the eifec'-v tive discharge surface of each electrode element@ I8 andthe two electrode rollers I0 beneath itis constantly changing so that if the high pcteiitlel impressed across the electrode structuresl 2@ and 4 remainedr constant, the potential gradient across .t each portion of the discharge zone 3 wouldfchanger'rcontinuallytdue to the rapid rotation" `of,'ele`c However, the source tif-'power is alternating,

. 5 andfthejpotential.across electrode structures 2 and. 4 therefore constantlychanges at a rate dependent uponfthexfrequency. Thus, there is a rapid fluctuation of potentialgradient Within the treatment zone between zero and a predetermined maximum which results from the high-frequency and thehighpeedrotatlonaof electrode elements I8. A tthe same' time, ftherdielectric constants of a package andJOi-air are :quite dilerent. Therefore, as .the potential gradient rises and a package moves throughthe treatment Zone, displacing air, the air in the treatment zone above and below the'plokage and surrounding the product within the :package is overstressed and discharges occur. However, due to the constantly .varying conditions, the potential gradient within the treatment zone will; soon fall toa valuelwhich is too low to' sustain the discharges.. `Consequently `these discharges are of extremely s hortlduration.

, Byadjustingthe vposition of: upper electrode structure 2 with respect .to the lower ,electrode structure 4 to determine` the dimensions of the treatment Zone, and then adjusting the high potential whichgis impressed. across the electrode structures 2 and. 4, the maximum potential within the --dischargezone'may-.be xed at a value to give maximumtreating eiciency for the particular :product .being treated; Also, the speed of rotation oflelectrode elements I8, the rate of movelnentlpf.` the materials being treated,'and `the other. factors, such asi-the .frequency of the high potential, may be changediwhen desirable.`

The high potential 1 between electrode structuresi-` and.-4may be'varied over wide ranges to suit particular.installations, but it has lbeen found that voltagesbetweenOOO and 200,000 are verykr satisfactory for certainluses.; In a like manner, the frequency of the-high potential may be varied, but a, frequency 0f approximately 1,000 cycles per second` has been found to be very satisfactory.; -Infv this. embodiment; upper electrodeV elements I 8 are; rotated at a. speed of approximately 3,500,351?, f

Asindicated above,the packages are generally sufrroundede byfairlv during treatment. Consequently, .the discharges partially ionize the air resulting in theformationof such products as ozone-and vcertain oxides. particularly oxides of nitrogen., These vproducts arel referred to herein provided whichfconstantly draws air in through-these openings; and discharges the airionization products from the .casing through a .Con/m1132581? pointed out I above, A during operation, the

eiective discharge isurfaces of the upper vvelectrode elements`r|v8; are ;constantlyy being changed, the

t packages 5 are being turned or rolled `(Figure 4) to r`change; the relationship between the various portions thereof and the discharges, and the electrodeaollersl arexbeing rotated. These constantjchangesfoffthe vdischarge surfaces and the materials associated with the discharges tend to maintain. uniform conditions within the treatment one by minimizing undesirable heating of theelectrodegelements.and they packages, and by tendingjtpgeljminate sustained ionization Qf i the vairwithinjtlie,zone.';

When packages 5 are moved through the treatf normal treatment of the other packages within the treatment; zone. 'Ihe provision of an individual condenser element 22 for each electrode roller `Ill limits the amount of current flowing through each electrode element, thus minimizing i such undesirable effects.

As pointed out above, the upper electrode assemblyunits (Figure 5) are mounted in alignment upon elongated frame 48, each unit having a rotatable portion including a pair of electrode velefments I8. In certain installations, the rotatable portions of alternate electrode assembly units rotate in one direction and the rotatable portions of the other electrode assembly units rotate in the opposite direction. Accordingly, as a pack- ,-age passes through the treatment zone, in the manner` described above, the individual discharges from one pair of electrode elements I8 tend to approach the walls of the package in one direction, while the individual discharges from i :the next succeeding pair of electrode elements I8 tend4 to approach the same walls of the package from the opposite direction.

This reversed rotation of the various pairs of electrode elements I8 is obtained by making all a-,of `the electrode assembly units identical, as

shown in Figure 5, and by placing the two arms 52 of two adjacent units side by side; thus assembled, two grooves |00 cooperate to form a conduit for the two pairs of leads 98 and 99. Under certain circumstances, it is desirable to rotate the electrodes on one side of frame 48 in one direction, and the electrodes on the other side of the frame in the opposite direction.

In this embodiment, there are illustratively six pairs, or a total of twelve, electrode elements I8, and twenty-four electrode rollers I0, there being a vertical condenser member 22 associated with each electrode roller I0. There is a particular relationship between the number of upper electrode elements I8 and the number of electrode rollers I0, which has been explained above; but it is understood that in certain installations, this relationship may not be desirable.

Figure 8 illustrates a modified form of the upper electrode elements which are mounted in thesame manner as electrode elements I8 and which may be used to advantage in certain installations. In this embodiment, the toroidal elements 200 arev undulated so as to provide a series of crests 202 and nodes 204. Crests 202 are the effective discharge portions of these electrode elements, and discharges occur when these crests approach the electrode elements II8 of the lower electrode structure. It will thus be seen that I have provided a -practical and effi-cient system and apparatus for accomplishing the several objects hereinabove mentioned as well as many others in a successful manner.

. As many possible embodiments may be made of themechanical features of the above invention and as the art herein described might be varied in various parts, all without departing from the scope of the invention, it is to be understood that all matter hereinabove set forth, `or shown in the accompanying drawings is to interpreted as illustrative and not in a limiting sense.

I claim:

1. In electrical apparatus in which a product to be treated is subjected to a discharge resulting from impressing a high potential across electrode elements, the combination of, an annular electrode mounted to rotate in a vertical plane and having an effective discharge surface which includes portions spaced radiallyand axially from each other.

2. In electrical apparatus in which a product to be treated is subjected to a discharge resulting from impressing a high potential across Aelectrode elements, the combination of, an annular electrode having an effective discharge surface area. the various portions of which are moved successively into and out of discharge position, said surface area having a portion which is substantially spiral in shape.

3. In electrical apparatus in which a product to be treated is subjected to a discharge resulting from impressing a high potential across `electrode elements, the combination of, an insulating support and an electrode structure supported thereby, said electrode structure comprising a group of individual electrode elements, an .elongated bracket supporting said individual electrode elements and metallic elements at the extremities of said bracket on opposite sides of said electrode elements.

4. In electrical apparatus in which a product to be treated is subjected to a discharge resulting from impressing a high potential Vacross elecj trode elements, the combination of, an electrode unit including a motor having a rotor and a stator, and rigidly carried by bracket means, and a pair of annular electrode shells mounted with said rotor, each of said shellshaving an eective discharge surface thereon a portion of which is substantially spiral in shape.

5. In electrical apparatus in which a product to be treated is subjected to a discharge resulting from impressing a high potential across electrode elements, the combination of,` a rotating electrode having its plane of rotation substantially at right angles to the path of movement of the product being treated, and a cooperatingY electrode structure having spaced cooperating discharge surfaces, said rotating electrode being non-symmetrical so that rotation thereof will cause a variation ofthe potential gradient within the discharge zone.

6. In electrical apparatus in which a product to be treated is subjected to a discharge result-V ing from impressing a high potential across electrode elements, the combination of, an upper elec-A trode having an effective discharge surface a portion of which extends substantially spirally, and a plurality of roller electrodes each of which cooperates with a` portion of said effective discharge surface. 7. In electrical treating apparatus, the combination of, means to move the product being 6 element Within said shell, and a body of small particles of a solid dielectric material surrounding said electrode element.

9. In electrical apparatus in Which a product to be treated is subjected to a discharge resulting from impressing a high potential across electrode elements, an annular electrode mounted to rotate in a vertical plane and having a toroidal eifective discharge surface which is swashed with its axis at an angle to the center of rotation.

10. In electrical apparatus in Which a product to be treated is subjected to a discharge resulting from impressing a high potential across electrode elements, an annular electrode mounted to rotate in a vertical plane and having a plurality of effective discharge surface portions which are spaced about the axis of rotation.

1l. In electrical apparatus in Which a product to be treated is subjected to a discharge resulting from impressing a high potential across electrode elements, the combination of, an annular 'electrode construction mounted to rotate about an axis which is substantially parallel to the direction of movement of the material being treated, said electrode construction having a plurality of effective discharge surface portions spaced radially about said axis and axially therealong.

l2. In electrical apparatus in which a product to be treated is subjected to a discharge resulting from impressing a high potential across electrode elements, the combination of, an annular electrode having an effective discharge surface area a portion of which is substantially spiral in shape, and means mounting said electrode to rotate about an axis which is substantially parallel to the discharge zone-whereby the various portions of said discharge surface `area are moved successively into and out of discharge position.

13. In electrical apparatus in which a product to be treated is subjected to a discharge resulting from impressing a high potential across electrode elements, the combination of, an insulating support and an electrode structure supported thereby, said electrode structure comprising a group of individual electrode elements, an elongated bracket supporting said individual electrode elements and metallic elements at the extremities of said bracket on opposite sides of said electrode elements, each of said metallic elements having an enlarged lower portion which is similar in shape to the contour of the effective portions of said electrode elements.

14. In electrical apparatus in which a product to be treated is subjected to a discharge resulting from impressing a high potential across electrode elements, the combination of, an electrode construction mounted to rotate about an axis which is substantially parallel to the path of movement of the material being treated, said electrode construction having a plurality of effective discharge surface portions which are spaced radially and axially about said axis in a definite pattern, and a plurality of elongated parallel electrodes Which are positioned to cooperate individually with said effective discharge surface portions.

15. In electrical apparatus in Which a product to be treated is subjected to a discharge resulting from impressing a high potential across electrode elements, the combination of, a rst electrode having an undulated effective discharge surface a portion of which extends substantially spirally,

and a plurality of parallel elongated cooperatingl electrodes extending substantially at right angles to the axis of said rst electrode-whereby various portions of said rst electrode successively cooperate with each of said elongated electrodes. 16. In electrical apparatus in which a product to be treated is subjected to a discharge resulting from impressing a high potential across electrode elements, the combination of, a pair of brackets, a fixed shaft extending between the ends of said brackets, a motor mounted upon said shaft and having a rotor With its axis substantially parallel to the path of movement of the material being treated, a pair of non-symmetrical electrode elements mounted with said rotor in a. symmetrical manner to form a balanced rotating unit- Whereby said electrode elements rotate together to move the various portions of their effective discharge surfaces into and out of discharge position.

- 1'7. In electrical apparatus in which a product to be treated is subjected to a discharge resulting from impressing a high potential across electrode elements, an electrode roller including, a shell of dielectric material having an opening at one end thereof, a metallic electrode element Within said shell having a connection through said opening and an enlarged portion at the end opposite said opening, and a body of small particles of a solid dielectric material surrounding said enlarged portion of said electrode element.

18. In electrical apparatus of the character described, an electrode roller comprising, an elongated shell of dielectric material having an opening extending from one end, a metallic element extending axially through said opening and substantially along the entire length of said shell, said metallic element including an electrode element positioned Within said `shell remote from said opening, solid dielectrical material sur-l rounding said electrode element, and sealing material `sealing said metallic element to the Walls of said 'shell at said opening and sealing said electrode element Within said shell.

19. In electrical treating apparatus, the combination of, a conveyor to move the product being treated in a given direction through the treatment Zone, a pair of dielectric bars positioned above and extending along said conveyor to deflect and guide the product during movement so that the product -actually moves along a path which varies from said given direction, and an elongated electrode structure extending above and parallel to said path. v

20. In electrical apparatus in which a product to be treated is subjected to a discharge resulting from impressing a high potential across electrode elements, an annular electrode mounted to rotate 

